This time you might begin by inspecting the enemy king (White's) and the constraints on its movement. Black’s bishop attacks h2, and g1 is off limits because White’s own knight is there. So the White king has very limited mobility, and this vulnerability is a tactical opening. If Black could just aim another piece at the king, he might have a mating threat; even if it were easily thwarted, it might enable him to win material by serving as the anchor for a double attack. Best of all would be to land an attacker on h2, since Black already covers that square with his bishop. His rook can prepare to do this with 1. …Rf2. This creates multiple threats at once, which is your general goal as a tactician. The first threat is that White’s queen is now attacked twice and guarded just once (by the knight on g1). If White’s queen moves, either to play QxQ or just to get someplace safer, Black also threatens to mate with Rh2. If White replies to Rf2 with QxR, then of course Black plays QxQ. White’s best reply probably is to play his own rook from d7 to d2, thus preparing to recapture, with a loss, after Black plays RxQ.